System for the packing of eggs



March 1961 M. LEHNER-STIRNEMANN 2,975,683

SYSTEM FOR THE PACKING OF EGGS 9 Sheets-Sheet 1 Filed July 16, 1959 lNVENTOR MAX LEHNER STIRNEMANN y BY ATTORNEYS March 1951 M. LEHNER-STIRNEMANN 2,975,683

I SYSTEM FOR THE PACKING OF EGGS Filed July 16, 1959 9 Sheets-Sheet 2 INVENTOR MAX LEHNERSTIRNEMANN ATTORNEYS March 1961 M. LEHNER-STIRNEMANN 2,975,633

SYSTEM FOR THE PACKING 0F EGGS 9 Sheets-Sheet 3 Filed July 16, 1959 IN, VENTOR MAX LEHNER-STIRNEMANN ATTORNEYS March 1961 M. LEHNER-$TIRNEMANN 2,975,633

SYSTEM FOR THE PACKING OF EGGS Filed July 16, 1959 9 Sheets-Sheet 4 INVENTOR MAX LEHNER-STIRNEMANN ATTORNEYS March 1961 M. LEHNER-STIRNEMANN 2,975,633

SYSTEM FOR THE PACKING OF EGGS Filed July 16, 1959 9 Sheets-Sheet 5 INVENTOR MAX LEHNER-STIRNEMANN ATTORNE-YS March 1961 M. LEHNER-STIRNEMANN 2,975,683

SYSTEM FOR THE PACKING 0F EGGS 9 Sheets-Sheet 6 Filed July 16, 1959 Ll ll...

|NVENTOR MAX LEHN'ER-STIRNEMANN BY y by ATTOR N EYS March 21, 1961 M. LEHNER-STIRNEMANN 2,975,683

SYSTEM FOR THE PACKING 0F EGGS Filed July 16, 1959 9 Sheets-Sheet 7 INVENTOR MAX LEHNER -$TIRNEMANN 9 l BY W M ATTORNEYS March 21, 1961 M. LEHNERSTIRNEMANN 2,975,683

SYSTEM FOR THE PACKING OF EGGS Filed July 16, 1959 9 Sheets-Sheet 8 INVENTOR MAX LEHNER-STIRNEMANN ATTORN EYS March 21, 1961 M. LEHNER-STIRNEMANN 2,975,683

SYSTEM FOR THE PACKING OF EGGS Filed July 16, 1959 9 Sheets-Sheet 9 INVENTOR MAX LEHNER -STIRNEMANN M BY ATTORNEYS 2,975,683 SYSTEM'FOR THE PACKING on EGGS Max Lehner-Stirnemann, Granichen, Switzerland Filed- July 16, 1959, Ser. No. 827,513

Claims priority, application Switzerland June 11, 1959 a 4 Claims. (Cl. 93- -37) This invention concerns a method for the packing of eggs and a system for carrying out such method.

The actual development of the self-service stores has greatly increased the demand for simple, shock-proof and light-weighted packings for eggs. Practice has further shown that such packings must absolutely prevent the falling out of the eggs. For example a packing may be used which is constituted by folding together a carton blank so as to form at. least one row of compartments formed by side panels each connected along a crease with a floor portion and by transverse partitions between said side panels, said packing being provided with relatively spaced transverse bridge members each connected along longitudinal creases on each side with a side panel and along a transverse crease with atransverse partition of which the sides are connected with the side panels by the formation on each side between said partition and the side panel of an inwardly folding flap. Each side panel forms a surface which is broken along a crease extending longitudinally about half way up its side in such a manner as to produce an outwardly projecting ridge, holding tabs formed by incisions being cut into the upper part nearest the bridge member of each panel in such manner as to project inwards from said creased ridge andto engage the rear faces of the flaps.

Heretofore with packings; of this type, the eggs have usually been placed inthe packing during the folding operationthereof before the packing was closed. This proceeding: has the substantial drawback that it requires a packing machine which, as is well-known is more expensive. than a folding machine.

The present invention has for. its object to provide a method for the packing of eggs. into packings from which they cannot fall' out. To this end" the method of the invention comprises the: steps of feeding at least a filling device the terminated packings on the one hand and the eggs appropriately aligned by aligning means on the other United States Patent-O Fig. 3 is a plan view showing the blank serving to form the packing;

Fig. 4 is a perspective front View of the folding machine in rest position;

Fig. 5 is a corresponding view of the upper portion of the folding machine with a packing engaged;

Fig; 6' is a plan' view of the upper portion of the folding machine with some parts removed for the sakeof clarity;

Fig. 7 is a section through the magazine of the folding machine with some parts removed;

Fig. 8 is a section taken through the upper portion of the folding machine in the position shown in Fig. 4;

Fig. 9 is a diagrammatical section taken along the line 9-9 in Fig. '8;

Fig. 10 is a diagrammatical section taken along the line a 1010 in Fig. 8;.

hand, the eggs being lodged in the compartments of the packing by the filling device whereby the packing ma terial is; resiliently displaced.

The invention further has for its object a system for carrying out this method, comprising a full automatic folding machine for the production of packing from flat blanks, conveying means including at least a conveying band for guiding said packings to at least a'fillingdevice, an aligning band associated to said filling device and adapted to feed eggs to be packed in proper alignment into the fillingdevice and further conveying means in cluding a conveying band forremoving the filled packings. Other features and advantages of the invention will become apparent from the description now to follow of a preferred embodiment thereof, given by way of example only, and in which reference will be had to the accompanying drawings, in which:

Fig. -11 is a diagrammatic view of asystem for carrying out-the-methodof the invention;

Fig.- 2 shows a closed packing;

Fig. 11 is a diagrammatical section taken along the line 11-41 in Fig. 8

Figs. 12 to 15 illustrate diagrammatically the relative positions of the folding members during the folding operation;

Fig. 16 is a perspective view showing the filling device;

Fig. 17 shows at a larger scale the conveying rail for the eggs, and

Fig. 18 illustrates a detail of the construction.

Figure 1 diagrammatically illustrates an installation or system for the packing of eggs. The flat blanks from which the packings willbe folded are stapled in a magazine 1*. Directly connected to this magazine lis a full automatic folding machine 2 in which the empty packings are folded, as will be described in detail hereafter. A conveyor 3' serves to remove the finished packings from the folding machine. Three conveyors 4 extend perpendicularly from the conveyor 3 and these conveyors 4 intui'n cooperate with three further conveyors 5 extendingiparallell'y to the conveyor 3. The conveyors 3' guide the empty packings to a point below the filling devices. designated by 6. The eggs to be packed into the packings are placed in a container 7 from which they are guided to a light-check device 8 and to directing bands 9; The light-check device 8 is of conventional construction including means such as photoelectric means for ascertaining and eliminating defective eggs. The aligning. bands 9 too areof conventional type. They serve to arrange the eggs with the pointed end in such position that this: end of the eggs is directed downwardly in the packing as will be described in more detail. later on. After the packings have been filled they leave the conveyors 5 for conveyors 10 feeding the filled packings to: a packing table 11. It would of course also be possible to provide the system with a further device 12 (interrupted lines) serving to fill the conventional tablets 13;

The: packings used in such installation are preferable of the type illustrated in Figs. 2 and 3. Such packings are formed from a carton blank with at least one, prefer- 15' each connected along a crease 16, with a floor portion '17 and with relatively spaced transverse bridge members 19 each connected along longitudinal creases 243 on each side with a side panel 15 and along a transverse crease 21 with a transverse partition 18 of which the sides are connected with the side panels 15 by the formation on eachside between said partition 18 and the side panel 15 of. an inwardly folding fiap 27. Each side panel 15 forms a surface Which is" broken along a crease 24 extending longitudinally about halfway up its side in such manner as to produce an outwardly projecting ridge, holding tabs 25 formed by incisions 26 being cut into the upper part 21 nearest the'bridge'member 19 of each side panel IS'iiH SUCh manner'as toproject inwards from said creased ridge-and toengage the rear faces of the flaps 27. The

floor panels 17 have lobed extensions 29 which are folded upwards out of the plane of the floor and extend in abutting flat contact upwards towards the bridge members. The lobed portions 29 are provided with incisions 31 for engaging the partitions 18 which are themselves provided with incisions 30 for engaging the lobes, the first incisions 31 in the partitions for engaging the lobes being upward,- ly bent at an angle of at least to the left and the right of the transverse axis of said partitions.

The fiat blanks (Fig. 3) are stapled in the magazine 1 and they are guided by means of not represented feeding means to the automatic folding machine 2 represented in detail in Figures 4 to 11.

Turning'now to these figures reference numeral 32 designates the machine frame of the folding machine rotatably housing a pair of feeding cylinders 33 conventionally driven to feed the fiat blanks from the magazine 1 to a supporting plate 34 of the folding machine 2. A pair of sleeves 35 secured to the plate 34 are slidable on a pair of guiding rods 36 so that the plate 34 with the sleeves 35 is vertically movable along said guiding rods 36. Abutments 37 at the upper ends of the guiding rods 36 are adjustable by means of nuts 38. In order to increase their stability these abutments are made from one piece with a web 39 connecting same. The guiding rods 36 are secured to a block 41 rigidly mounted in the machine frame 32 by means of screws 40. Pressure springs 42 arranged about the guiding rods 36 and hearing on the one hand against the block 41 and on the other hand against the plate 34 tend to press the latter against the abutments 37.

In the block 41 there are further mounted a pair of guiding sleeves 43 serving to guide a pair of rods 44. The lower ends of these rods 44 are connected with a plate 45 to which are secured two further guiding sleeves 46 arranged coaxially and concentrically with respect to the guiding sleeves 43. The guiding sleeves 43 and 46 are surrounded by pressure springs 47 tending to maintain the rods 44 in the lower position (Fig. 7). At their upper ends the rods 44 carry a plate 48 to which are secured folding fingers 49 engaging, upon relative movement between the plate 34 and the plate 48, slots 50 in plate 34 (Fig. 8). A further plate 52 rigidly secured to the block 41 between the plate 48 and the plate 34 is provided with slots 51 for the folding fingers 49. This plate 52 carries holding fingers 53 each pivotally mounted about a horizontal pin 54. These holding fingers 53 are loaded by not represented springs in counterclockwise direction in Figures 7 and 8. In their rest position shown in Figure 7 the holding fingers 53 each abut against a roll 55 provided at the adjacent folding finger. Upon upward movement of the folding fingers 49 the holding fingers 53 will be pivoted in clockwise direction by the rolls 55 owing to their vL-shape and will be pressed against the folding finger 49 lying at their right in Figures 7 and 8. The plate 52 carries four holders 56 of which only two are visible in Figures 7 and 8. A further holding finger 57 is pivotally mounted on each of said holders 56. A spring 58 tends to maintain the holding finger 57 in the position shown in Figure 7. Upon downward movement of the plate 34 the holding fingers 57 pass a slot 50 whereby the rim of the plate 34 moves the holding fingers 57 over a roll 59 and an arm 60 against the action of the springs 58 (Figs. 5, 8).

Two two-arm levers 69 are pivotally mounted about pins 70 on the block 41. The upright arm of each lever 69 is provided with a hook 71 retaining the plate 34 in the lower position thereof (Fig. 8). To this end the plate 34 is provided with rolls 72. The horizontally extending arms 73 of the levers 69 serve, as will be described later on, to release the plate 34. The holding levers 69 are loaded by springs 74.

A main drive shaft 61, rotatably mounted in the machine frame 32 is driven over a chain wheel 62 and a chain 63 from a not represented motor (Fig. 4). This 4 main drive shaft carries a cam 64 controlling the up-anddownward movement of plate 48. An axle 65 also mounted in the machine frame 32 carries a freely rotatable intermediate lever 66 having a feeler 67 cooperating with the cam 61. The intermediate lever is secured with its other end to plate 45 by means of a bolt 68.

A movable bridge member or yoke 75 is secured above the plate 34 by means of four rods 76. This yoke is provided with further holding fingers 77 directed downwardly. The rods 76 are held in guidings 78 secured to the machine frame 32 as shown in Figures 4 and 5. The lower ends of the rods 76 are secured to a stirrup 79 (Fig. 9) the middle web 79 of which carries a laterally directed feeler 80. This feeler 80 engages an arcshaped guiding slot 81 of a lever 82 freely rotatable on an axle 100. The pivotal movements of lever 82 are controlled from a cam 84 over a further feeler 83' arranged on a lever 82a. To this end the lever 82a is provided with a further feeler engaging the cam track 85 of cam 84. The lever 82a is mounted for rotation on an axle 94. The earns 84 are provided each with an abutment 86 cooperating with the arm 73 of the levers 69 to release the plate 34.

Two pairs of folding blades 87 and 88 are further arranged in the machine frame 32. These blades have not been represented in Figure 6 for the sake of clarity.

The blades 87 are rotatably mounted in the frame 32. At their right-hand end (Fig. 6) they carry a pinion 89 meshing with a toothed wheel 90. The toothed wheels 90 are rotatably mounted in the machine frame 32 and are interconnected by means of a reverse lever 91 (Fig. 9). One of said toothed wheels 90 is connected by a rod 92 with an arm 93 freely rotatable on an axle 94 of the machine frame. The arm 93 carries a feeler cooperating with a cam 95 mounted on the main drive shaft 61.

The folding blades 88 are similarly mounted for rotation in the machine frame 32 and they carry at their left-hand end (Fig. 6) a pinion 96 meshing with a toothed wheel 97 mounted in the machine frame. Arms 98 connect these toothed wheels 97 with a lever 99 freely rotatable on an axle 65 (Fig. 11). A further lever 101, mounted on an axle 94a is provided with two feelers 102 and 103. The feeler 102 provided at the end of lever 101 engages the lower side of lever 99 and the feeler 103 cooperates with a cam 104 mounted on the main drive shaft. 7

The operation of the described automatic folding machine will now be described previous to the description of the filling devices 6.

The folding of a packing, i.e. the formation of the closed packing shown in Figure 2 from the carton blank illustrated in Figure 3 is effected infour operations. Figures 12 to 15 diagrammatically show the relative positions of the yoke 75, of the plate 34, of the plate 52, of the folding blades 87, 88 and of the blank.

With all elements in their rest position (Figs. 4 and 12) the fiat blank arrives over the feeding cylinders 33 onto plate 34. At this precise moment the main drive shaft 61 starts to rotate whereby the cam 84 rotating with said shaft pivots lever 82 in clockwise direction (Fig. 9) resulting over the stirrup 79 and the rods 76 in a downward movement of the yoke 75. Thereby the holding fingers 77 contact the flat blank along the transverse bridge members 19 and press it against plate 34. Upon further rotation of the cam 84 the yoke 75 presses the plate 34 downwardly against the action of the springs 42. In their lowermost position the levers 69 loaded by the springs 74 snap-in and secure the plate 34 in this position (Fig. 8 position of the yoke shown in dot-anddash lines).

Before the end of this downward movement the plate 45 is upwardly moved by the cam 64. The folding fingers 49 traverse the slots 50 and erect the transverse partitions 18. Simultaneously the rolls 55 pivot the holding fingers 53 in clockwise. direction (Fig. 8.) so that said holding fingers press the erected'partitions 18 against the back of the folding finger 49 at the right thereof (Figs. 5, 10, 13). Simultaneously too, the holding fingers 57 are pivoted. and:he1d in pivoted positionby the plate 34 '(Fig. 8). They thereby maintain the first and the last bridge member 19 pressed against the plate 43. R

In addition to the holding fingers 77 the yoke 75 further carries pre-folding fingers 105. In the lowermost position of the yoke (Fig. 13) these pro-folding fingers 105 fold the lateral walls of the packing along the crease 24. Thereby the inner edge of the folding blades 88 which at this moment is directed upwardly, serves as backing (Fig. 13).

The further rotation of the earns 34 results'in an upward movement of the yoke 75. Already during this upward movement the folding blades 87 enter into action. The cam 95 pivots the lever 93 in counterclockwise direction (Fig. 9) andthe rod 92 rotates the left toothed wheel 90 in counterclockwise direction too, while the right-hand toothed wheel is rotated in counterclockwise direction over the reverse lever 91. Thus both of the folding blades 87 are pivoted inwardly. The edge I of the lobed extensions 29 abuts the gripping elements 1116 of the folding blades 87 so that said extensions 29 are folded about the crease 28 by the movement of the folding blades 87 (Figs. 5, 9 position on dot-and-dash lines in Fig. 14).

Upon still further rotation of the main drive shaft 61- the folding blades 87 are pivoted outwardly while the cam 1G4 rotates the folding blades 88 inwardly over the lever 99, arms 98 and'the toothed wheels 97 (dot-anddash lines Fig; 11, Fig. 15). Thereby the folding blades 88 press the extensions 29 into the partitions so that the packing is closed. The abutments86 pivot the arms 69 outwardly thereby releasing plate 3.4 which under the action of the springs 42 returns into its original position.

All elements and members now are in the position shown in Figures 4 and 6. The closed packing lies on plate 34 with its floor portion 17 turned up and with the bridge members 19 in contact with plate 34.

Not represented'means which may be constituted by appropriate grippers now bring this closed packing to the conveyor 3 onto which they are placed in reverse position, i.e. with the crease 16 directed downwardly and with the bridge members directed upwardly.

From the conveyors 3 the finished packings are guided by the conveyors 4' and 5 under the filling devices 6. One such filling device is diagrammatically represented in Figures 16 to 18. It comprises a frame 107 in which is mounted an electrornotor 108. From the aligning band 9 the eggs 109 arrive laterally into the device 6 over a collecting sheet 110. After passing a movable contact 111 the eggs are led to a pair of guidings 1 12,

113. These guidings- 112, 113 are secured to the arm 114 of a two-arm lever 114, 115. This lever 114, 115 is pivotally mounted in the frame 107. Its arm 115 is connected over a member 116 witha lever 117 also mounted in frame 107. This last-mentioned lever 107 carries a roll 1 18 cooperating with a cam 119' whereby a spring 117 presses the lever 117 and its roll against this cam 119. The cam 119' is mounted on a shaft 120 driven by motor 108 over an electromagnetic coupling 1.

second electromagnetic coupling 126. The upper side of rail 122 is provided with angle members 127 for the eggs 169. A further rail 128 is secured to the frame 107 so as to extend along the rail 122. An electrical contact 129 is adjustable on this further rail 128. Its end 130 is so arranged as to lie above the guiding 113 so as to. be depressed by the conveyed eggs. Along the guiding 113 but extending below it there are provided guiding channels 131 below which the packing ready to be filledris placed on the conveyor 5. The frame 107 further carries a stirrup 132 which is pivotally mounted and provided with counter weights 133. This stirrup is provided with punches 134 which, in the pivoted position of the stirrup are adapted to press the eggs 109 from the guiding channels into the packing. The stirrup 132 is connected by means of an arm 135 (Fig. 18) with a lever 136 mounted in the frame 107. This lever 136 carries a roll 137 cooperating with a cam 138 which is also mounted on the shaft 120. 7

When the first egg 109 rolls over the contact 111 it is guided on the first angle member 127 of rail 122 in position I. The pulse produced by contact 111 actuates the coupling 126 and the eccentrics 124 effect one revolution in clockwise direction whereafter the coupling 126 is again disengaged. The egg then is situated on the first part of the guidings 112, 113 in positionII (Fig. 17). This operation is repeated for each egg 109 until the first egg after position III has attained position IV, in which the contact end 130 is depressed. This results in the engagement of coupling 121 and shaft 129 effects one revolution whereafter the coupling 121 is again disengaged. The cam 119 causes the arm 114 to pivot in clockwise direction (Fig. 16) whereby the eggs are led into the guiding channels 131. During the return movement of the guidings 112, 113the cam 138 causes the stirrup 132 to pivot and the punches 134 thereof press the eggs 109 into the compartments or. cells 14 of the first row of the packing. I The conveyor 5 now advances about the breadth of a row of compartments and the described operation is repeated. According to the number of compartments of the packing the movable contact 129 may be adjusted so that the tilting movement of the guidings 112, 113 occurs at the desired moment.

In the preceding description the drive for the different devices and machines has not been explained and represented in detail. The drives for'the diflerent conveying bands, for the feeding means of the magazine, for the folding machine and for the filling devices are of course synchronized in conventional manner.

The described packing method affords for substantial advantages. As already mentioned it permits the use of a folding machine instead of the heretofore required packing or wrapping machine. Thus it was made possible to develop a full automatic folding machine of rapid and reliable operation as no parts thereof come into contact with the fragile goods to be packed. This folding machine further presents the advantage of folding the blank to the finished packing at a sole workin'g station, while in the known machines the blank is guided through several pre-, afterand endfolding stations, between which the eggs are inserted in the semi-terminated packing.

The filling device with its punches may work very fast as it has been found out that the eggs are particularly resistant when the pointed end is downwardly directed when the eggs are pressed into the packing. The

'conveyor 5 could also be driven continuously and the checking has substantial drawbacks as it makes necessary the removal and re-opening of a closed packing for one bad egg in it. With a check of the eggs previous to their packing this drawback is avoided.

What I claim is:

1. A machine for folding a carton blank for forming a packing of the type having transverse partitions connected to side panels which are joined along a fold with floor portions which are connected along another fold with lobed extensions forming a median longitudinal partition and wherein each side panel forms a surface broken along a further fold; this machine comprising a machine frame, a block rigidly mounted in said frame, a supporting plate mounted on and movable relatively to said block and to which the flat blanks are fed and movable from a blank receiving to a blank folding position, said plate being biased toward its blank receiving position, a second plate mounted on said block below said supporting plate and movable relatively both to the block and to the supporting plate, a yoke movably mounted in the machine frame above the supporting plate and provided with holding fingers and prefolding means including fingers for folding the sidepanels along said further fold and the floor portions along the other fold, said holding and prefolding fingers being directed downwardly, means including folding fingers secured to the second plate for erecting the transverse partitions out of the plane of the blank by engagement therewith upon relative movement between the supporting plate and the second plate, slots in said supporting plate, first means including folding blades for folding the lobed extensions along the other fold, second means including folding blades for closing the packing by pressing the folded lobed extension into the transverse partitions, and a main driving shaft carrying the cam means controlling the movements of the yoke and the folding blades,

2. A machine for folding a carton blank for forming a packing of the type having transverse partitions connected to side panels which are joined along a fold with floor portions which are connected along another fold with lobed extensions forming a median longitudinal partition and wherein each side panel forms a surface broken along a further fold; this machine comprising a machine frame, a block rigidly mounted in said frame, a supporting plate mounted on and movable relatively to said block and to which the flat blanks are fed and movable from a blank receiving to a blank folding position, said plate being biased toward its blank receiving position, a second plate mounted on said block below said supporting plate and movable relatively both to the block and to the supporting plate, a yoke movably mounted in themachine frame above the supporting plate and provided with, holding fingers and'prefolding means including fingers for folding the side panels along said further fold and the floor portions along the other fold, said holding and prefolding fingers being directed downwardly, means including folding fingers secured to the second plate for erecting the transverse partitions out of the plane of the blank by engagement therewith upon relative movement between the supporting plate and the second plate, slots in said supporting plate, a third plate secured to said block having holding fingers pivotally mounded thereon which are biased against said folding fingers and cooperate therewith to clamp the erected transverse partitions between them and the backs of the folding fingers upon relative movement between the second plate and said third plate, first means including folding blades for folding the lobed extensions along the other fold, second means including folding blades for closing the packing by pressing the folded lobed extension into the transverse partitions, and a main driving shaft carrying cam means controlling the movements of the yoke and the folding blades.

3. A machine for folding a carton blank for forming a packing of the type having transverse partitions connected to side panels which are joined along a fold with floor portions which are connected along another fold with lobed extensions forming a median longitudinal partition and wherein each side panel forms a surface broken along a further fold; this machine comprising a machine frame, a block rigidly mounted in said frame, a supporting plate mounted on and movable relatively to said block and to which the fiat blanks are fed and movable from a blank receiving to a blank folding position, said plate being biased toward its blank receiving position, a second plate mounted on said block below said supporting plate and movable relatively both to the block and to the supporting plate, a yoke movably mounted in the machine frame above the supporting plate and provided with holding fingers and prefolding means including fingers for folding the side panels along 'said further fold and the floor portions along the other fold, said holding and prefolding fingers being directed downwardly, means including folding fingers secured to the second plate for erecting the transverse partitions out of the plane of the blank by engagement therewith upon relative movement between the supporting plate and the second plate, slots in said supporting plate, a third plate secured to said block having holding fingers pivotally mounted thereon which are biased against said folding fingers and cooperate therewith to clamp the erected transverse partitions between them and the backs of the folding fingers upon relative movement between the second plate and said third plate, further holding fingers pivotally mounted on holders fixed to said third plate, each further holding finger being provided with an arm and a roll cooperating with the rim of the supporting plate for pivoting said further holding fingers upon downward movement of said supporting plate, first means including folding blades for folding the lobed extensions along the other fold, second means including folding blades for closing the packing by pressing the folded lobed extension into the transverse partitions, and a main driving shaft carrying cam means controlling the movements of the yoke and the folding blades.

4. The machine of claim 1 comprising two-arm levers pivotally mounted on pins secured to said block, each lever being provided on one arm with a hook for retaining said supporting plate against the biasing of said supporting plate and in its blank folding position, said levers being biased in plate retaining position, and releasing means carried by said cam means and cooperating with the second arms of said levers for pivoting said levers against the biasing of said levers so that the supporting plate is released and reset to its blank receiving position.

References Cited in the file of this patent UNITED STATES PATENTS 1,810,156 Brandenburg June 16, 1931 2,068,144 McAleer Jan. 19, 1937 2,242,304 Johnson May 20, 1941 2,656,659 Buechek Oct. 27, 1953 2,701,938 Murray Feb. 15, 1955 2,895,274 Mumma July 21, 1959 

